2 files changed, 19 insertions, 7 deletions

diff --git a/src/lib/libc/net/res_mkquery.c b/src/lib/libc/net/res_mkquery.c
index 61595a6e8c..e414b5060d 100644
--- a/src/lib/libc/net/res_mkquery.c
+++ b/src/lib/libc/net/res_mkquery.c
@@ -1,4 +1,4 @@
-/*      $OpenBSD: res_mkquery.c,v 1.9 2001/06/11 10:06:00 itojun Exp $  */
+/*      $OpenBSD: res_mkquery.c,v 1.10 2001/07/31 22:02:18 jakob Exp $  */
 
 /*
  * ++Copyright++ 1985, 1993
@@ -60,7 +60,7 @@
 static char sccsid[] = "@(#)res_mkquery.c       8.1 (Berkeley) 6/4/93";
 static char rcsid[] = "$From: res_mkquery.c,v 8.5 1996/08/27 08:33:28 vixie Exp $";
 #else
-static char rcsid[] = "$OpenBSD: res_mkquery.c,v 1.9 2001/06/11 10:06:00 itojun Exp $";
+static char rcsid[] = "$OpenBSD: res_mkquery.c,v 1.10 2001/07/31 22:02:18 jakob Exp $";
 #endif
 #endif /* LIBC_SCCS and not lint */
 
@@ -221,8 +221,17 @@ res_opt(n0, buf, buflen, anslen)
         cp += INT16SZ;
         *cp++ = NOERROR;        /* extended RCODE */
         *cp++ = 0;              /* EDNS version */
-        __putshort(0, cp);      /* MBZ */
-        cp += INT16SZ;
+        if (_res.options & RES_USE_DNSSEC) {
+#ifdef DEBUG
+                if (_res.options & RES_DEBUG)
+                        printf(";; res_opt()... ENDS0 DNSSEC OK\n");
+#endif /* DEBUG */
+                __putshort(DNS_MESSAGEEXTFLAG_DO, cp);  /* EDNS Z field */
+                cp += INT16SZ;
+        } else {
+                __putshort(0, cp);      /* EDNS Z field */
+                cp += INT16SZ;
+        }
         __putshort(0, cp);      /* RDLEN */
         cp += INT16SZ;
         hp->arcount = htons(ntohs(hp->arcount) + 1);
diff --git a/src/lib/libc/net/res_query.c b/src/lib/libc/net/res_query.c
index db76821fc6..3cf7928302 100644
--- a/src/lib/libc/net/res_query.c
+++ b/src/lib/libc/net/res_query.c
@@ -1,4 +1,4 @@
-/*      $OpenBSD: res_query.c,v 1.15 2001/06/27 00:58:55 lebel Exp $    */
+/*      $OpenBSD: res_query.c,v 1.16 2001/07/31 22:02:18 jakob Exp $    */
 
 /*
  * ++Copyright++ 1988, 1993
@@ -60,7 +60,7 @@
 static char sccsid[] = "@(#)res_query.c 8.1 (Berkeley) 6/4/93";
 static char rcsid[] = "$From: res_query.c,v 8.9 1996/09/22 00:13:28 vixie Exp $";
 #else
-static char rcsid[] = "$OpenBSD: res_query.c,v 1.15 2001/06/27 00:58:55 lebel Exp $";
+static char rcsid[] = "$OpenBSD: res_query.c,v 1.16 2001/07/31 22:02:18 jakob Exp $";
 #endif
 #endif /* LIBC_SCCS and not lint */
 
@@ -123,8 +123,11 @@ res_query(name, class, type, answer, anslen)
 
         n = res_mkquery(QUERY, name, class, type, NULL, 0, NULL,
                         buf, sizeof(buf));
-        if (n > 0 && (_res.options & RES_USE_EDNS0) != 0)
+        if (n > 0 && ((_res.options & RES_USE_EDNS0) ||
+            (_res.options & RES_USE_DNSSEC))) {
                 n = res_opt(n, buf, sizeof(buf), anslen);
+        }
+
         if (n <= 0) {
 #ifdef DEBUG
                 if (_res.options & RES_DEBUG)